Syringe assembly

ABSTRACT

A syringe assembly including a barrel and an externally mounted squeeze bulb. The squeeze bulb provides a mounting sleeve surrounding the barrel adjacent the wide mouthed end of the barrel. A lock ring compressively biases the mounting sleeve into sealing engagement with the barrel to resist withdrawal of the bulb from the barrel.

United States Patent Rentsch [54] SYRINGE ASSEMBLY [72] Inventor: Hans J. Rentsch, Deerfield, Ill.

[73] Assignee: Medline Industries, Inc.

[22] Filed: Sept. 17, 1970 [21] Appl. No.: 73,006

[52] US. Cl ..128/232, 128/247 [51] Int. Cl. ..A61m 1/00 [58] Field of Search ..128/231, 232, 233, 224, 247, 128/239; 222/562, 567570, 213, 215, 206;

[56] References Cited UNITED STATES PATENTS 2,596,083 6/1952 Wahlbeck ..128/247 X 3,486,503 12/1969 Porter et al ..128/247 X [451 Dec. 12, 1972 1,971,345 8/1934 Hein ..128/231 FOREIGN PATENTS OR APPLICATIONS 178,343 10/1921 Great Britain ..128/232 710,302 1/l966 Italy ..128/232 Primary Examiner-Richard A. Gaudet Assistant Examiner-J. Yasko Attorney-Dressler, Goldsmith, Clement & Gordon [5 7] ABSTRACT A syringe assembly including a barrel and an externally mounted squeeze bulb. The squeeze bulb provides a mounting sleeve surrounding the barrel adjacent the wide mouthed end of the barrel. A lock ring compressively biases the mounting sleeve into sealing engagement with the barrel to resist withdrawal of the bulb from the barrel.

1 Claim, 2 Drawing Figures PATENTED DEC 12 1912 lNVE/VTOP 5y Hans J Berzfsc/ a9 SYRINGE ASSEMBLY This invention relates to a syringe assembly in which locking means are provided for sealingly securing a squeeze bulb to the main body of a syringe barrel. The locking means take the form of a sleeve-like lock ring defining a continuous inner surface for sealingly clamping the bulb to the barrel. 7

There are a variety of squeeze bulb syringe assemblies presently on the market for medical use. In each of these a resilient squeeze bulb is sealingly secured to a syringe barrel, the bulb being squeezable to discharge a measured or calibrated amount of fluid from the syringe assembly.

In such squeeze bulb assemblies the barrel is elongate and generally tubular and terminates in a nozzle at one end. The other end defines a wide-mouthed opening to which the squeeze bulb is secured. In some such assemblies a squeeze bulb mounting sleeve is inserted into the wide-mouthed openingto sealingly engage the barrel internally. Such barrel and sleeve assemblies are frequently difficult to disassemble, especially when a separate sleeve insert is used in an effort to assure proper sealing and retention.

In other syringe assemblies a squeeze bulb mounting sleeve is dimensioned to sealingly grip the external surface of the barrel adjacent the wide-mouthed opening. To assure proper sealing, seating and retention of a bulb in such assemblies it has been sometimes necessary to so dimension the squeeze bulb sleeve that it is difficult to assemble and disassemble. In other instances, where a very tight fit is not provided, sometimes the bulb has become dislodged accidentally.

In accordance with this invention, means for securely maintaining the telescopically assembled relationship of a squeeze bulb and barrel are provided. These means resist withdrawal of the bulb from the syringe barrel.

The barrel defines a mounting hub portion at its wide-mouthed end, the end remote from the discharge nozzle. Desirably the barrel defines an annular external rib or lip. The squeeze'bulb provides a generally tubular mounting sleeve proportioned to receive the mounting hub portion in a sealing fit. Desirably the mounting sleeve defines an internal annular recess to complementarily receive the annular lip.

The mounting sleeve is preferably tapered externally, increasing in diameter as the squeeze bulb portion is approached.

A continuous tubular lock ring is proportioned to be telescopically seated on the mounting sleeve. The internal surface of the lock ring is generally complementary in configuration to the external surface of the mounting sleeve and is so proportioned in size that it gradually reaches a tight compressive fit with the sleeve. At that point it biases the mounting sleeve into tight sealing engagement with the underlying barrel hub segment. Thereby it also creates frictional forces resistant to telescopic disassembly of the bulb and barrel. Where an annular lip and interlocked sleeve recess are present, the overlying lock ring tends to prevent their disengagement, further enhancing the resistance of the bulb and barrel to disassembly.

The lock ring itself is easily moved into sealing engagement with the sleeve and is easily removed. This then provides a very simple, but unique and highly ad vantageous syringe assembly.

Further advantages, objects and features of this in vention will become apparent from the following description and drawings of which:

FIG. 1 is a side elevational view, partially in section, of a syringe assembly of this invention; and

FIG. 2 is an exploded view, partially in section of the component parts of FIG. 1.

Referring now to the drawings, an irrigator syringe assembly 10 of this invention comprises a barrel member 12, a hollow sanitary elastomeric squeeze bulb assembly 14 and a lock ring l6. I

Barrel member 12 comprises a suitably calibrated elongate tubular barrel segment 20 and a frustoconical end portion 22 which terminates in a coaxial tubular nozzle 24. At its other end barrel segment 20 terminates in a mounting hub 26 circumscribed by an annular lip 28. I

Bulb assembly 14 comprises a generally spherical hollow squeeze bulb segment 30 with an axial depression 32 at one end. Depression 32 may be used as a stand for the assembly 10. At its other end, bulb segment 30 terminates in a mounting sleeve 34 which is generally cylindrical in shape. lntemally tubular sleeve 34 is generally complementary in configuration and sizeto mounting hub 26. Sleeve 34 defines an annular recess 36 which is complementary to and adapted to receive annular lip 28, and further provides an annular shoulder 38 adjacent the recess 36 to assist in limiting telescopic movement of the bulb assembly 14 downwardly along mounting hub 26 when bulb assembly 14 is telescopically assembled to barrel member 12.

Lock ring 16 is continuous and is generally cylindrical in configuration externally and preferably defines an annular bead 40 or other external gripping means to facilitate its movement into locking engagement with the barrel member and bulb assembly. lntemally lock ring 16 is generally complementary in configuration to the external surface configuration of mounting sleeve with which it coacts, and as'such in the embodiment illustrated defines a generally frustoconical internal surface 42.

The three elements are shown :in exploded view in FIG. 2 ready for assembly into theirpositions illustrated in FIG. 1. To assemble the members, the mounting sleeve 34 of bulb assembly 14 is seated upon the mounting hub 26. Preferably the fit is a resilient gripping one which means that the internal diameter of sleeve 34 is slightly less than the external diameter of hub 26. Telescopic assembly of the bulb and barrel is limited by the interlocking engagement of annular lip 28 and annular recess 36, and further by the engagement of the shoulder 38 with the u pperend of the barrel adjacent lip 28.

In a typical syringe assembly of this invention, a barrel assembly is molded of transparent polystyrene. The mounting hub of the barrel is about 1.34 inches in diameter externally and is about 0.44 inches long. The

bulb is molded of synthetic rubber, such as a styrenebutadiene block copolymer made by Shell Chemical Company under the designation Kraton 2109, having a wall thickness of about 0.09 inches. The largest internal diameter of the bulb is about 2.13 inches. The internal diameter of the bulb mounting sleeve is about 1.33 inches. The external surface of the mounting sleeve tapers from a diameter of about 1.45 inches to about 1.60 inches adjacent the squeeze bulb segment.

The lock ring assembly is molded of a medium impact polystyrene and defines an inner surface about 0.5 inch wide which tapers from a diameter of about 1.44 inches to about 1.53 inches thereby to assure a tight compressive sealing fit with the bulb mounting sleeve when assembled as illustrated in FIG. 1.

To clamp the bulb and barrel to each other in their telescopically assembled relationship and to maintain that relationship, lock ring assembly 16 is moved into engagement with mounting sleeve 34 from the nozzle end of the barrel. The tapered confronting outer surface of sleeve 34 and surface 42 of lock ring 16 are gradually forced tighter together until the compressed telescopically sealed position illustrated in FIG. 1 is reached. At this point lock ring 16 exerts sufficient force against the sleeve, hence against the interlocked interface between sleeve 34 and hub 26 so that withdrawal of the sleeve and removal of the bulb is exceedingly difficult. So also does the lock ring assembly assure the sealing of the bulb sleeve against the barrel hub 26 thereby to prevent leakage of liquid from barrel opening 44.

This simple, but highly effective mode of maintaining the bulb-barrel relationship greatly improves over prior art syringe assemblies, many of which relied upon the frictional engagement between a hub and sleeve, sometimes externally, and frequently with a sleeve received internally of the barrel. In the former assemblies the assembly was not always reliably connected. In the latter assemblies removal of the bulb from the syringe barrel was frequently excessively difficultv The use of an externally mounted bulb with a friction lock ring in accordance with this invention provides a simple but highly effective irrigator syringe assembly.

What is claimed is:

l. A syringe assembly comprising an elongate tubular syringe barrel for containing a volume of liquid, said barrel providing a mounting hub portion, a tubular discharge nozzle, and an intermediate elongate body, a hollow elastic squeeze bulb defining a tubular mounting sleeve seated on said mounting hub portion, and means for resisting withdrawal of said mounting sleeve from said mounting hub, said means comprising a tubular continuous lock ring, said lock ring circumscribing said mounting sleeve and resiliently urging said mounting sleeve into tight frictional sealing engagement with said mounting hub, said lock ring being telescopically movable without deformation thereof over said discharge nozzle, over said body and over said mounting hub portion, and into said circumscribing position and in which said barrel defines an annular lip and said bulb sleeve defines an annular recess complementary to and receiving said lip, said locking ring overlying said lip and said recess, and in which the external surface of said mounting sleeve is tapered and increased in diameter toward said squeeze bulb portion and said lock ring defines a tapered interior surface which decreases in diameter to urge said mounting sleeve into frictional engagement with said mounting hub, said locking ring defining external gripping means for facilitating movement of said locking ring into and out of locking engagement with said mounting sleeve.

UNITED STATES OFFICE- E CERTIFICATE OF CORRECTION Patent No. 3,705,583 Dated December 12, 1. 972

Inventor(s) Hans J. Rentsch It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Claim 1, column 4, line 24 "increased" should be increases Signed and sealed this 8th day of May l973 BBL-MED M. 'i-"1'JE'iCI-IER,J11. ROBERT GOTTSCHALK Attesting Officer Commitssioner of Patents 

1. A syringe assembly comprising an elongate tubular syringe barrel for containing a volume of liquid, said barrel providing a mounting hub portion, a tubular discharge nozzle, and an intermediate elongate body, a hollow elastic squeeze bulb defining a tubular mounting sleeve seated on said mounting hub portion, and means for resisting withdrawal of said mounting sleeve from said mounting hub, said means comprising a tubular continuous lock ring, said lock ring circumscribing said mounting sleeve and resiliently urging said mounting sleeve into tight frictional sealing engagement with said mounting hub, said lock ring being telescopically movable without deformation thereof over said discharge nozzle, over said body and over said mounting hub portion, and into said circumscribing position and in which said barrel defines an annular lip and said bulb sleeve defines an annular recess complementary to and receiving said lip, said locking ring overlying said lip and said recess, and in which the external surface of said mounting sleeve is tapered and increased in diameter toward said squeeze bulb portion and said lock ring defines a tapered interior surface which decreases in diameter to urge said mounting sleeve into frictional engagement with said mounting hub, said locking ring defining external gripping means for facilitating movement of said locking ring into and out of locking engagement with said mounting sleeve. 